Minutes from the Federal Reserve’s June meeting suggest there is a growing gap between officials who believe U.S. inflation could remain too low for the Fed’s comfort and those who believe a spike in consumer prices could be closer than forecasters think.

Some policy makers “expressed concern about the persistence of below-trend inflation,” the minutes said. Indeed, a couple even suggested the central bank might have to let unemployment fall below its long-term normal rate in order to ensure inflation moves back toward the 2% target.

That sentiment was far from unanimous, however. “Some others expected a faster pickup in inflation or saw upside risks to inflation expectations because they anticipated a more rapid decline in economic slack.”

The divergence may help explain why Fed officials are concerned the historically low volatility seen in financial markets of late suggests investors may be underpricing risk.

“Low implied volatility in equity, currency and fixed-income markets, as well as signs of increased risk-taking, were viewed as an indication that market participants were not factoring in sufficient uncertainty about the path of the economy and monetary policy,” the minutes said.

That’s like the Fed telling markets: “We don’t know what we’re doing so how can you be so sure?”

Which is why some Fed policy makers like San Francisco Fed President John Williams actually believe the central bank’s controversial dot chart is useful despite the potentially mixed messages it offers. He told reporters during a recent press briefing that he believed the range of forecasts conveyed an appropriate level of uncertainty that he hopes market participants will pick up on.

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